A short list of various assemblers for the various PIC microncontrollers. Was originally written around 2004, so is a little out of date.
Multi-OS assemblers
These are assembler available for multiple operating systems in source code and compiled versions. Most will have been ported to the Linux platform.
PICASM (http://www.iki.fi/trossi/pic/)
When I used to do PIC software development on the Amiga, I used this assembler.
It works well and the C-code is easily portable. There is a port of this software for the Amiga on AMinet that I did a long time ago.
Devices supported:
12c508, 12c509, 12c671, 12c672, 16c52, 16c54(a), 16c55, 16c56, 16c57, 16c58a, 16c61, 16c62(a), 16c63, 16c64(a), 16c65(a), 16c66, 16c67, 16c71, 16c710, 16c711, 16c715, 16c72, 16c73(a), 16c74(a), 16c83, 16c84, 16f84 16c620, 16c621, 16c622, 16c554(a), 16c556a, 16c558(a), 14000
GPASM (http://gputils.sourceforge.net)
This is the main PIC development package for the Linux platform
The GPUTILS package includes gpasm (the assembler), gplink (linker) and gplib (PIC librarian)
There is also the GPSIM simulator available from the same author.
There is extensive device support by the assembler/linker, too long to list here.
Windows/DOS
MPASM (www.microchip.com)
This is part of the MPLAB package from Microchip. It is possible to use MPASM without MPLAB if you desire. From what I recall, you can install the DOS version of the tools from the latest version. As it ia from Microchip, it supports every PIC type.
PIC Assemblers for the Amiga
PICasm/DevPIC @ Aminet programmer included
APIC Package @ aminet Also Programmer and simulator
Empic @ Aminet Programmer and assemlber for disk drive port. Link to my page.
PicKit @ Aminet, Assembler, programmer and debugger.